Friction brake



FRICTION BRAKE Y Filed April'l9, 1926 Patented Sept. 3,1929.

. I I t 122L043 NT OFF-ICE,

Jam-es s. :rnomrson, on NEW YORK, N. Y., ASSIG'NOR T0 AMERIfiAiv BRAKE MA 7 TERIALS conrona'rron, or LNEW YORK, N. 'Y., A conrona'rron or nnw YORK.

I ,"rmo'rxon BRAKE.

j- Application filed April 19,1926. Serial No. 102,828:

This invention relates to friction brakes and while it is particularly. adapted for ex% pandingbrakes tomake frictional contact with a-drum, which is a form of brake commonly employed in automotive vehicles, it isalso useful in many other installations as will be apparent to those skilled in theart.

The invention has for its object generally to provide an efficient brake for automotive vehicles and other installations which will provide desired'braking friction and pre vent the accumulation of destructive. heat in service in the brake drum or in other parts of the brake assembly or in parts associated therewith. I

A further object of the invention is to reduce the friction contact area of-the braking member with the member'to be braked in a brake assembly and to ventilate the parts so that the heat of friction will be quickly dissipated and will not-accumulate or become stored in the brake assembly-or travel by con-.

drum.

Fig. 4 is a detailed view of a slotted drum. I have embodied the invention in different types .of brake assemblies but for the purpose of this application I have selected one type among those which have been found to be satisfactory and wherein two brake heads are arranged within a perf ated drum and carry composition shoes to frictionally'contact with.

the rim of the drum. The heads 5, {rare pivoted at one end on studs 6, (Land are operated by a cam 7 which engages their free These heads may .be made in various shapes and designs but I prefer to make them skele-Q ton in'form as more particularlyset forth in my application, Serial No. 92,048 filed- March 3, 1926. Friction shoe 8 'is detachably secured on each head by-clamps 9 and the seat on the head for this shoe is preferably skele ton in form to permit a clrculation 'of air around and beneath the shoe, but for-some purposes it will entirely satisfactory to also to the fact that little if any opportunity 110 I have musj cationsSerial No.1 00,298 and Serial No. 100,- 299,filedApril7, 1926.

The drum 10 has its rim 11' provided with or in the form of slots '13. The numberand provide a substantially solid-seat on the head for'the shoe, as shown'in my co pending applizso a number of perforations which may be in i the form of substantially round openings 12 various conditions butigenerally: speaking I desire to provide tlie rini with as many and as large openings :as many conveniently be employed without reducing the strength ofthe drumto a point where-it will become dis- 'torted by application of thebrake in service and thus reduce its efiiciency and-life. a

I may use-a shoe ofany kind suitable at.

the purpose butIpreferto use tac'ompositionshoe with or without ametal back 14, as may.

be found desirable to'satisfy different condi= tlons. The shoe is preferably made reversible end for end on its seat and I prefer to make it of a composition which is wear resistant and heat resistant. 4

The invention is simple 'in form and is adapted to be embodied in different types and for use in difierent installations. The primary object of the, invention is to get rid of the friction heat as quickly as possible after it is produced so that it will not mjuriously affeet any of the parts of'the brake or travel to other parts where it may cause inconvenience. and damage. I have restricted the contact area of the shoe materially as compared with the contact area of the braking members now enerally employed for'similar service and I ave reduced the size of the head to a comparatively. skeleton form and I have perforated the rim of the drum with which the shoe contacts so that with all of these changes I ob-' tain an efiici'ent circulation of air around and above. the, shoe, the head and the drum and thereby provide for ventilating the brake assembly-to prevent the accumulation of. heat therein and to prevent the travel of heat from the brake assembly to the rim of the wheel or other parts with which the brake is associ-.'. ated. .Itis said that rubber tires on heavyautomotive vehicles are being damaged by heat conducted 01" radiated from' the brakes, and this is due, I believe, to the fact that in the ordinarybrakes the friction heat is distributed when produced over a large area of the braking member and the member to be braked,

- for many different installations.

where replacement is necessary. My inven-i tion avoids these disadvantages because, 1n the first place, it restricts the contact between the braking member and the member to be braked,

I to a small area where frictionheat is produced and thus leaves a. large proportion of the rim of the drum free from contact at any one time .member to be braked, the rim of the'drum,-is perforatedso that the heat of friction will be dissipated quickly and will not accumulate in the drum or other parts of the brake assem-- bly. The combination between the shoe of restricted area and the perforated drum is novel and highlysatisfactory, and together with the skeleton head provides a brake assembly which is comparatively light in weight, which is efiicient in service, and which is adaptable The perforated drum and the skeleton head .and'the shoe of restricted area separately and collectively not only provide for ventilating the brake assembly and the parts thereof, but they also providefor and co-operate in main: -taining the brake assembly clean and free fromaccumulationof the products of the. I

with the shoe and the contact surface of the road. The perforated drum is important in this respect because any dirt collecting on the drum surface will be cleaned therefrom by contact with the shoe and will fall through the-openings in the drum'or be discharged at one side of the drum. The shoe'contact surface willalways be maintained in a clean condition because any dirt which might accumulate between the contact surfaces will be discharged through the perforations in the drum.

I am awarethat changes may be made in the form, construction and arrangement of parts of my invention, for example, other forms of fastening means may be employed for securing the shoe on the head; the perforated drum :as shown'dn my application, Serial No.

100,300, filed April 7, 1926 may be used and I reserve the right to make all changes which fall within the scope of the following claim,

I claim:'- 4

In a friction 'brake the combination of .a brake drum having-a rim provided with a plurality of perforations extending therethrough, a friction shoe comprising a. solid im- .perforate composition body, and means for movingsaid shoe relative to the drum to carry the body of the shoe into and out of frictional contact with the rim, the contact area of the body being-less than one-quarter of the contact area of the rim.

Y JAMES srnoiriason. 

